Active sites and mechanisms for H₂O₂ decomposition over Pd catalysts

Anthony Plauck; Eric E Stangland; James A Dumesic; Manos Mavrikakis

doi:10.1073/pnas.1602172113

Active sites and mechanisms for H₂O₂ decomposition over Pd catalysts

Proc Natl Acad Sci U S A. 2016 Apr 5;113(14):E1973-82. doi: 10.1073/pnas.1602172113. Epub 2016 Mar 22.

Authors

Anthony Plauck¹, Eric E Stangland², James A Dumesic³, Manos Mavrikakis³

Affiliations

¹ Department of Chemical and Biological Engineering, University of Wisconsin, Madison, WI 53706;
² Core R&D-Inorganic Materials and Heterogeneous Catalysis, The Dow Chemical Company, Midland, MI 48674.
³ Department of Chemical and Biological Engineering, University of Wisconsin, Madison, WI 53706; jdumesic@wisc.edu emavrikakis@wisc.edu.

Abstract

A combination of periodic, self-consistent density functional theory (DFT-GGA-PW91) calculations, reaction kinetics experiments on a SiO2-supported Pd catalyst, and mean-field microkinetic modeling are used to probe key aspects of H2O2 decomposition on Pd in the absence of cofeeding H2 We conclude that both Pd(111) and OH-partially covered Pd(100) surfaces represent the nature of the active site for H2O2 decomposition on the supported Pd catalyst reasonably well. Furthermore, all reaction flux in the closed catalytic cycle is predicted to flow through an O-O bond scission step in either H2O2 or OOH, followed by rapid H-transfer steps to produce the H2O and O2 products. The barrier for O-O bond scission is sensitive to Pd surface structure and is concluded to be the central parameter governing H2O2 decomposition activity.

Keywords: catalysis; density functional theory; hydrogen peroxide; microkinetic analysis; palladium.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't